Field of the Invention
The invention relates to a vehicle body having a strutting configuration in the vicinity of the floor of the vehicle body.
In order to improve the torsional and flexural rigidity of self-supporting or unit-construction vehicle bodies, additional strutting configurations are fitted in the region of the underbody of the vehicle body. This is practiced particularly in the case of open vehicles, in order to reduce torsional vibrations about the longitudinal axis of the vehicle and in order to reduce transverse bending of the vehicle end, because the stiffening action of the vehicle roof is missing in the case of open vehicles. However, stiffening struts are also used in the case of closed vehicles in order to impart the necessary stiffness to lightweight constructions, at points which are particularly stressed.
European Patent No. EP 0 603 536 B1 discloses a vehicle body for a sports car which has outer, lateral longitudinal members in the region of a passenger cell. The longitudinal members extend into a rear engine compartment and, in the region of the rear wheels, are tapered toward the longitudinal central axis of the vehicle and are offset upward. A V-shaped stiffening configuration which is formed from two struts and the tip of which points in the direction of the vehicle rear is fastened to the lateral longitudinal members. The stiffening configuration extends from the vehicle underbody in an essentially horizontal manner on the rear side. In this case, the tip of the stiffening configuration is supported via further stiffening struts against the longitudinal members bounding the engine compartment. The further stiffening struts are likewise disposed in a V-shaped manner, when viewed in a vertical plane transverse with respect to the longitudinal direction of the vehicle. As a result, a spatial double-V-configuration is produced, the tips of which converge in a point in a longitudinal central plane of the vehicle.
A further self-supporting vehicle body or unit-construction body having stiffening struts in the floor region is disclosed in German Patent No. DE 39 05 650 C2. The body includes outer, lateral longitudinal members in the floor region of a passenger compartment and further longitudinal members which are offset toward the central axis of the vehicle and upward and extend to a front engine compartment. In this case, the stiffening struts bridge the transition between the longitudinal members in the region of the front wheel arch apertures and are positioned at an angle of approximately 45 degrees with respect to the longitudinal central axis of the vehicle without being connected to one another. Each of these hi struts is fastened at one end to one of the outer, lateral longitudinal members. The other end is fastened to a crossmember, which is attached in the region of the engine compartment to the longitudinal members and extends below an engine approximately in the region of the wheel arch apertures. This results mainly in an increased rigidity in the transitional region of the longitudinal members at the height of the wheel arch apertures.
Further strut configurations for stiffening a vehicle body in the floor region are disclosed, for example, in Published, Non-Prosecuted German Patent Application No. DE 31 39 458 A1 or German Patent No. DE 767 141 PS.
Furthermore, U.S. Pat. No. 5,417,454 discloses a vehicle body having diagonally disposed strutting devices in the vicinity of the floor. The strutting devices extend from a crossmember, which is fastened on the end side of the longitudinal members of a main frame, to a further crossmember situated in front of it. This measure is intended to obtain a reduction in vibrations in the vehicle floor.
Furthermore, a motor vehicle having a planar stiffening element is disclosed in Published European Patent Application No. EP 0 941 912 A1. The stiffening element spans the space between the longitudinal members and extends as far as a front crossmember at the front end of the motor vehicle and is essentially fastened to the longitudinal members and to the front crossmember.
It is accordingly an object of the invention to provide a vehicle body which overcomes the above-mentioned disadvantages of the heretofore-known vehicle bodies of this general type and which has an improved torsional and flexural rigidity.
With the foregoing and other objects in view there is provided, in accordance with the invention, a vehicle body, including:
a main frame including an underbody and two longitudinal members, the main frame defining a longitudinal vehicle direction, a transverse vehicle direction and a vehicle end region;
the longitudinal members extending from the underbody to the vehicle end region such that the longitudinal members are offset upwardly with respect to the underbody;
an auxiliary frame fastened to the main frame and extending from the underbody toward the vehicle end region;
a crossmember fastened to the longitudinal members at the vehicle end region;
the crossmember having a downwardly projecting connecting section disposed substantially level with the auxiliary frame and extending substantially horizontally in the transverse vehicle direction;
the longitudinal members having respective end sections, the connecting section having axial ends and turning, at the axial ends, into upwardly extending sections extending from the axial ends of the connecting section to the end sections of the longitudinal members; and
a strutting configuration extending substantially horizontally from the auxiliary frame toward the vehicle end region, the strutting configuration having a first end fastened to the auxiliary frame at locations spaced apart from one another in the transverse vehicle direction, and the strutting configuration having a second end fastened to the connecting section of the crossmember.
In other words, the object of the invention is achieved by a vehicle body having a strutting configuration in the vicinity of the floor, the vehicle body including a main frame having it two longitudinal members which run to one end of the vehicle and are offset upward with respect to a vehicle underbody, an auxiliary frame which is fastened to the main frame and continues the underbody of the main frame in the direction of the end of the vehicle, a crossmember which is fastened to the longitudinal members in the end region of the vehicle and has a connecting section which projects downward to the ground side, extends essentially horizontally in the transverse direction of the vehicle and is disposed essentially level with the auxiliary frame and which merges at its axial end in each case into a section, which extends essentially vertically or is inclined upwardly, and leads to an end section of one of the longitudinal members, and the vehicle body including a strutting configuration, which essentially horizontally continues the auxiliary frame in the direction of the vehicle end, is fastened with one end thereof to the auxiliary frame, at points which are spaced apart from one another in the transverse direction of the vehicle, and is fastened with the other end thereof to the connecting section of the crossmember.
This allows shifting the fastening position or articulation position of the strutting configuration, which is fastened to a component of high structural rigidity, relatively far toward the front end or rear end of the vehicle. This results in a further improvement in the static and also dynamic rigidity in a region of the front part of the vehicle or rear part of the vehicle which is in the vicinity of the floor and is important for the vibration behavior of the entire vehicle.
Furthermore, a particularly space-saving construction of the crossmember is obtained, such that the construction does not obstruct units or auxiliary units to be positioned, for example, in the region of the engine compartment.
Especially when relatively heavy masses are to be attached to one end of the vehicle, the configuration according to the invention substantially reduces torsional vibrations and thus the vehicle body is stabilized in the transverse direction of the vehicle. By reinforcing the front end of the vehicle or the vehicle rear, vibrations of the longitudinal members to and fro in the transverse direction in a horizontal plane of the vehicle are also reduced. The solution according to the invention is suitable in particular for providing a stiffening configuration which can be retrofitted in a simple manner to a mass-produced vehicle whose basic version is a closed vehicle with a roof structure and whose body is used as a basis for an open vehicle without a roof structure.
According to a preferred embodiment of the invention, the installation outlay of the entire, additional stiffening configuration, which is formed of the crossmember and the strutting configuration, can be reduced by providing the crossmember as a one-piece element.
According to an advantageous embodiment of the invention, the strutting configuration is formed by two struts which converge toward one another in a V-shaped manner in a direction toward the vehicle end. This provides an additional stiffening effect which is obtained in an advantageously simple manner. In particular, it is also possible to easily retrofit a configuration of this type onto a finished vehicle.
The struts are preferably articulated in a common point on the crossmember. As a result, the struts can be connected to the crossmember in a single working step without requiring a great outlay.
According to an alternative embodiment of the invention, the strutting configuration is embodied as a flat thrust frame which is fastened to the crossmember along the connecting section extending in the transverse direction of the vehicle. This provides a particularly high stiffening effect that extends all the way to the vehicle end. The thrust frame can also be used for closing off an engine compartment toward the ground side.
In order to save weight, the strutting configuration is preferably configured as an essentially rectangular outer frame having diagonal struts.
In accordance with another advantageous embodiment of the invention, the strutting configuration can be produced in a particularly simple manner if the strutting configuration is configured as a one-piece sheet-metal element having four triangular recesses which are positioned in the manner of a clover leaf and, for example, can simply be punched out of the sheet-metal element.
In a further advantageous embodiment of the invention, wheel carriers for the wheels of a vehicle axle are supported on the auxiliary frame such that the auxiliary frame is situated below the wheel axes whereas the longitudinal members extend over the wheel axes. This produces a cage-like construction of high rigidity surrounding, for example, the engine compartment or trunk of a vehicle. The auxiliary frame fulfills the dual function of supporting the wheel carriers of the wheels of a vehicle axle and of an additional transverse stiffening of the vehicle body in the region of the wheel arc apertures.
The auxiliary frame is preferably fastened to a section of a floor panel which is disposed between the longitudinal members. This measure allows the auxiliary frame to be fastened to a section of the underbody of the main frame, wherein this section of the underbody is positioned as far as possible toward the end of the vehicle where the longitudinal members already bend upward. In comparison with the conventional stiffening configurations explained above, the length which is to be spanned by the strutting configuration and, in particular, by the stiffening struts between the various sections of the main frame therefore remains short, so that a good reinforcement or stiffening of the front part or rear part of the vehicle is obtained. Moreover, the free clearance of the vehicle is not adversely affected.
In accordance with a further advantageous embodiment of the invention, an end frame is fastened to the free ends of the longitudinal members, the end frame extending in an essentially vertical orientation in a plane transverse to the longitudinal direction of the vehicle. In case the end frame is a front end frame, the latter is used for holding the lighting equipment and, if appropriate, a radiator of the vehicle. The end frame can be fitted in its entirety as a constructional unit onto the front ends of the longitudinal members.
The crossmember is preferably disposed as an independent component directly next to the end frame, on a side toward the vehicle, in the longitudinal direction of the vehicle. In other words, the crossmember is disposed directly adjacent to the end frame such that the end frame is disposed behind the crossmember when looking from the auxiliary frame along the longitudinal vehicle axis toward the crossmember.
However, according to an alternative embodiment, the crossmember is also fastened to the end frame itself. This permits a strength-optimized reinforcement of the end frame. Furthermore, it is possible to pre-assemble the crossmember together with the end frame then to fasten this unit to the free end sections of the longitudinal members.
The crossmember is preferably integrated in the front end frame and forms a one-piece element with the latter, with the result that the previously described pre-assembly step can be omitted.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a vehicle body having a strutting configuration in the vicinity of the floor, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.